Correct api base name in kafkaResourceIT reactive tests

[iconben]

When generating a reactive service (e.g. gateway), api base name in KafkaResourceIT tests does not match the actual api base name, which leads to integration tests fail eventually.

In generated Resource class, api is:

@RestController
@RequestMapping("/api/<%= dasherizedBaseName %>-kafka")
public class <%= upperFirstCamelCase(baseName) %>KafkaResource {

    @PostMapping("/publish/{topic}")
    public ........

in generated rest tests, it was :

    @Test
    void producesMessages()<% if (!reactive) { %> throws Exception<% } %> {
        <%_ if (!reactive) { _%>
        restMockMvc.perform(post("/api/<%= dasherizedBaseName %>-kafka/publish/topic-produce?message=value-produce"))
            .andExpect(status().isOk())
            .andExpect(content().contentType(MediaType.APPLICATION_JSON));
        <%_ } else { _%>
        client.post().uri("/api/jhipster-kafka/publish/topic-produce?message=value-produce")
            .exchange()
            .expectStatus().isOk()
            .expectHeader().contentType(MediaType.APPLICATION_JSON);
        <%_ } _%>
        ......
    }

When non-reactive, the api path is right though. The path should be nothing to do with if reactive or not.

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[DanielFran]

Thanks @iconben for the contribution